System for collecting and diluting pulp for analysis

ABSTRACT

A system and process for continuously extracting and diluting a pulp sample from a pulp production line for the purpose of conducting near real time analysis of pulp fibers while mitigating the loss of production due to outdated sample data and the amount of pulp extracted for analysis but not utilized. The system comprises several inline mixers and pulp and dilution lines configured to successively dilute an initial pulp sample for analysis while collecting waste for re-concentration and re-introduction into the production pulp line.

RELATED APPLICATION

This application claims the benefit under 35 U.S.C. § 119(e) to the provisional patent application number 62/618,302 filed on Jan. 17^(th), 2018, the entirety of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION Technical Field

The present disclosure relates generally to fiber analysis and more particularly to systems and processes for collecting and diluting fibers for analysis in the pulp, paper, and nonwovens industries.

Related Art

Pulp from lignocellulosic biomass is the primary ingredient in many useful products. Pulp mill operators typically produce pulp from raw materials in one of three ways, i.e. (1) through chemical pulping, (2) through mechanical pulping, or (3) through a hybrid approach using techniques from both chemical pulping and mechanical pulping. Pulp mill operators may sell the pulp to various downstream mill operators, who produce the pulp into useful articles including for example paper of various qualities and grades, tissue papers, packaging material, filler material, and absorbent materials.

No matter the primary or secondary production process, operators employ technicians to sample the pulp at various production stages. These technicians evaluate the pulp's physical and chemical qualities. This practice allows operators to infer final product's quality; and, if needed, allows the operators to adjust process conditions to obtain desired qualities.

Typically, operators pressurize the pulp in a pulp line, so operators or technicians extract a small sample of pulp through a burst nozzle to minimize pressure loss. The operators or technicians then transfer the sample to a lab or other testing facility. Analytical equipment producers typically calibrate their analytical equipment to evaluate pulp samples at a specific concentration. If the sample is too concentrated, the sample will clog the equipment. If the sample is too dilute, the analysis equipment will not return useful data. For example, a technician may use an image analyzer configured to measure the average length of pulp fibers. To do this effectively, the image analyzer, or the person operating the image analyzer, should be generally able to see and record the lengths of individual fibers.

The pulp sample from the pulp line is typically at a higher concentration than the concentration at which the analytical equipment functions. Therefore, technicians manually dilute the sample to the desired concentration prior to testing. However, this practice of collecting and preparing samples in batches can create significant delay between collection, analysis, data interpretation, and process condition adjustment. That is, the samples tend to represent pulp that has passed through the process possibly hours before. The represented pulp that was around the burst nozzle at the time the technician took the sample may be waiting in a storage vessel or may already be incorporated into a final product by the time mill operators adjust process conditions based upon the sample analysis. In extreme cases, if the sample results indicate that the represented pulp did not meet mill or customer standards, the product may be discarded or sold at a lower price, thereby resulting in significant production loss.

In addition to batch samples not being representative of the current pulp at the sample source, collecting samples in batches increases the risk that a particular sample may not be representative of the pulp. Whether due to human error, contamination, or a mixing fluke, the batch sample may have never represented the surrounding pulp, or an error in the testing processes may have rendered the resulting data non-representative of the pulp in the line. Therefore, the batch practice further increases the risk that mill operator will adjust operating conditions based upon inaccurate data, thereby potentially producing an inferior product and resulting in production loss.

SUMMARY OF THE INVENTION

As can be seen, the batch testing practice creates a problem of delay in extracting, analyzing, evaluating, and utilizing pulp data to adjust process conditions. The batch practice also increases the risk that decisions will be made based on upon inaccurate data. To address these problems, Applicant has conceived an exemplary serial pulp dilution system as more fully described herein.

An exemplary continuous serial pulp dilution system may comprise: a pulp source, a first sample conduit configured to transfer an initial pulp sample from the pulp source to a first inline mixer, a dilution fluid source, a first dilution conduit configured to transfer a dilution fluid to the first inline mixer, wherein the dilution fluid and the initial pulp sample mix in the first inline mixer to create a first dilute pulp solution, a second pulp sample conduit configured to transfer a portion the first dilute pulp solution from the first inline mixer to a second inline mixer, a first withdraw conduit configured to withdraw a remaining portion of the first dilute pulp solution from the first inline mixer, a second dilution conduit configured to transfer the dilution fluid from the dilution source to the second inline mixer, wherein the dilution fluid and the first dilute pulp solution mix in the second inline mixer to create a second dilute pulp solution being more dilute than the first dilute pulp solution, a third pulp sample conduit configured to transfer a portion of the second dilute pulp solution from the second inline mixer to a third inline mixer, a second withdraw conduit configured to withdraw a remaining portion of the second dilute pulp solution from the second inline mixer, a third dilution conduit configured to transfer the dilution fluid from the dilution source to the third inline mixer, a fourth pulp sample conduit configured to transfer a portion of the third dilute pulp solution from the third inline mixer to a fourth inline mixer, a third withdraw conduit configured to withdraw a remaining portion of the third dilute pulp solution from the third inline mixer, and a fourth dilution conduit configured to transfer the dilution fluid from the dilution source to the fourth inline mixer, wherein the dilution fluid and the portion of the third dilute pulp solution mix in the fourth inline mixer to create a fourth dilute pulp solution being at least 650 times more dilute than the initial pulp sample.

It is contemplated that previous attempts to create a continuous dilution system may have been hindered by the amount of water or other dilution fluid needed to dilute the pulp sample to concentrations that analytical equipment could interpret. A continuous analytical system has a continuous flow of sample into the piece of analysis equipment at the desired concentration. For example, if the analytical equipment is configured to process a pulp sample at a concentration of 25 microliters (“μL”) of pulp per liter (“L”) every minute (“min”), (collectively, 25 μL/L per min.) and if the technicians pulled a liter of initial pulp sample having a 4% concentration every minute, the technicians would need to use 1,600 L of dilution fluid every minute to dilute the initial pulp sample to the desired concentration for the analysis equipment.

Others may have been dissuaded from attempting a continuous dilution system in the pulp and paper industries due to this enormous amount of dilution fluid required and the considerable amount of waste such a system would generate.

Without being bounded by theory, it is contemplated that the stepwise or serial approach used by the exemplary systems and processes described herein may allow operators or technicians to collect pulp samples continuously while minimizing the amount of water needed to dilute the initial sample. Furthermore, by directing a portion of the diluted sample to a waste collection tank after each dilution step, the exemplary systems and methods described herein may mitigate dilution fluid waste.

Systems and processes in accordance with the present disclosure may allow operators to “singularize” pulp fibers for analysis, that is, the pulp sample may be brought to a low consistency (e.g. about 0.0025% pulp fiber to dilution liquid) from a pulp source, wherein the initial pulp sample from the source has a consistency about 4% to about 6% pulp per dilution fluid.

It is contemplated that the systems and processes described herein may allow operators to conduct near real-time analysis of physical and chemical pulp properties while the pulp is still in the production line and thereby allow mill operators to adjust process conditions in response to the analysis to produce pulp, paper, or other pulp-based products of desired quality.

Exemplary systems described herein may further obviate the need for burst nozzles, or other wear parts configured to control the egress of pulp from the pulp line for purposes of sample collection. Pulp can be abrasive, and the pulp may wear on burst nozzles over time, thereby resulting in production loss due to leaking and shutdown for repair.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing will be apparent from the following more particular description of exemplary embodiments of the disclosure, as illustrated in the accompanying drawings. The drawings are not necessarily to scale, with emphasis instead being placed upon illustrating the disclosed embodiments.

FIG. 1 is a schematic representation of an exemplary pulp sample dilution system comprising four inline mixers.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description of the preferred embodiments is presented only for illustrative and descriptive purposes and is not intended to be exhaustive or to limit the scope and spirit of the invention. The embodiments were selected and described to best explain the principles of the invention and its practical application. One of ordinary skill in the art will recognize that many variations can be made to the invention disclosed in this specification without departing from the scope and spirit of the invention.

Similar reference characters indicate corresponding parts throughout the several views unless otherwise stated. Although the drawings represent embodiments of various features and components according to the present disclosure, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate embodiments of the present disclosure, and such exemplifications are not to be construed as limiting the scope of the present disclosure.

Except as otherwise expressly stated herein, the following rules of interpretation apply to this specification: (a) all words used herein shall be construed to be of such gender or number (singular or plural) as to circumstances require; (b) the singular terms “a,” “an,” and “the,” as used in the specification and the appended claims include plural references unless the context clearly dictates otherwise; (c) the antecedent term “about” applied to a recited range or value denotes an approximation within the deviation in the range or values known or expected in the art from the measurements; (d) the words “herein,” “hereby,” “hereto,” “hereinbefore,” and “hereinafter,” and words of similar import, refer to this specification in its entirety and not to any particular paragraph, claim, or other subdivision, unless otherwise specified; (e) descriptive headings are for convenience only and shall not control or affect the meaning or construction of any part of the specification; and (f) “or” and “any” are not exclusive and “include” and “including” are not limiting. Further, the terms, “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including but not limited to”).

References in the specification to “one embodiment,” “an embodiment,” “an exemplary embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

To the extent necessary to provide descriptive support, the subject matter and/or text of the appended claims is incorporated herein by reference in their entirety.

Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range of within any sub ranges there between, unless otherwise clearly indicated herein. Each separate value within a recited range is incorporated into the specification or claims as if each separate value were individually recited herein. Where a specific range of values is provided, it is understood that each intervening value, to the tenth or less of the unit of the lower limit between the upper and lower limit of that range and any other stated or intervening value in that stated range or sub range hereof, is included herein unless the context clearly dictates otherwise. All subranges are also included. The upper and lower limits of these smaller ranges are also included therein, subject to any specifically and expressly excluded limit in the stated range.

It should be noted that some of the terms used herein are relative terms. For example, the terms “upper” and “lower” are relative to each other in location, i.e. an upper component is located at a higher elevation than a lower component in a given orientation, but these terms can change if the device is flipped. The terms “inlet' and “outlet” are relative to a fluid flowing through them with respect to a given structure, e.g. a fluid flows through the inlet into the structure and flows through the outlet out of the structure. The terms “upstream” and “downstream” are relative to the direction in which a fluid flows through various components, i.e. the flow of fluids through an upstream component prior to flowing through the downstream component.

The terms “horizontal” and “vertical” are used to indicate direction relative to an absolute reference, i.e. ground level. However, these terms should not be construed to require structure to be absolutely parallel or absolutely perpendicular to each other. For example, a first vertical structure and a second vertical structure are not necessarily parallel to each other. The terms “top” and “bottom” or “base” are used to refer to locations/surfaces where the top is always higher than the bottom/base relative to an absolute reference, i.e. the surface of the Earth. The terms “upwards” and “downwards” are also relative to an absolute reference; an upwards flow is always against the gravity of the Earth.

FIG. 1 is a schematic representation of a preferred embodiment of an exemplary serial pulp dilution system 100. The exemplary serial pulp dilution system 100 comprises a pulp source 102 and a dilution fluid source 134. A first sample conduit 108 has a first end 103 engaging the pulp source 102 and a distal end 113 engaging a feed end 109 of a first inline mixer 110. In this manner, the first sample conduit 108 fluidly communicates with the pulp source 102 and the first inline mixer 110 and is thereby configured to convey an initial pulp sample 115 from the pulp source 102 to the first inline mixer 110. Similarly, a first dilution conduit 128 _(a) has a first end 133 engaging the fluid source 134 and a distal end 143 engaging the feed end 109 of the first inline mixer 110. In this manner, the first dilution conduit 128 _(a) fluidly communicates with the fluid source 134 and the first inline mixer 110. The first dilution conduit 128 _(a) is thereby configured to convey a dilution fluid 125 from the fluid source 134 to the first inline mixer 110. Unless otherwise specified, “conduits” are understood to have a first end (see for example, 103, 135, and 145), and a distal end (see for example 113, 137, and 147) distally disposed from the first end. The respective ends engaging separate elements (for example, the pulp source 102, first inline mixer 110, withdraw line tank 124, etc.) in the exemplary system 100 allow the conduits to fluidly communicate with the named elements and thereby convey a substance (for example an initial pulp sample 115, dilute pulp solutions 127, 160, 170, 180, dilution fluid 125, etc.) between the named elements.

In operation, the first sample conduit 108 conveys an initial pulp sample 115 from the pulp source 102 to the first inline mixer 110. The pulp source 102 may be any source of pulp and may include pulp lines in a pulp mill, or a tank of pulp in a laboratory for example. It is contemplated that the exemplary serial pulp dilution system 100 may be disposed at several locations in a pulp mill and may be configured to tap a pulp line at several locations along a pulp line to evaluate changing characteristics of the pulp fibers as the fibers progress through the production process.

If desired, operators may tap a pulp source 102 continuously for an initial pulp sample 115. A pump 104 pumps the initial pulp sample 115 through the first sample conduit 108. The pump 104 may be configured to pump the initial pulp sample 115 through the entire serial pulp dilution system 100 together with a dilution pump 138 if desired. The system 100 further comprises a first valve V1 through which operators may control the rate at which the initial pulp sample 115 enters the first inline mixer 110.

The initial pulp sample 115 desirably moves through the first sample conduit 108 as a slurry. The consistency of the initial pulp sample 115 may vary depending upon the production process and the type of pulp produced. In certain exemplary processes, the initial pulp sample 115 may be a low consistency pulp sample in which about 10 percent of the initial pulp sample 115 is pulp fibers, the remainder being dilution fluid 125. In other exemplary systems and processes, the initial pulp sample 115 may be diluted to having a 10 percent pulp fiber concentration prior to entering the serial dilution system 100.

The exemplary serial pulp dilution system 100 may further comprise a recirculation conduit 106 fluidly communicating with the first sample conduit 108 and the pulp source 102. The recirculation conduit 106 transports a portion of the initial pulp sample 117 from the first sample conduit 108 back to the pulp source 102. By returning excess initial pulp sample 117 to the pulp source 102, the recirculation conduit 106 reduces production loss due to continuous sample collection.

A first inline mixer 110 disposed downstream of the pulp source 102 has a discharge end 111 distally disposed from the feed end 109 along a body 105. Several baffles 107 are disposed within the body 105. The inline mixers 110, 120, 130, and 140 may be static inline mixers, meaning that the baffles 107 are static and that the initial pulp sample 115, and portions of the first dilute pulp solution 127 _(a), second dilute pulp solution 160 _(a), third dilute pulp solution 170 _(a), and fourth dilute pulp solution 180 _(a) (collectively, “pulp sample”) mix along the length of each inline mixer 110, 120, 130, 140 due to the flow of the pulp sample through the inline mixers 110, 120, 130, and 140 and the turbulence created by the baffles 107. Static inline mixers may be preferable because the static inline mixers do not require an external power source to mix the pulp samples.

However, in other exemplary embodiments, the inline mixers 110, 120, 130, and 140 may be dynamic inline mixers characterized by having mixing elements (e.g. baffles, mixing arms, rotary blades, or other elements disposed in the inline mixer 110, 120, 130, and 140 configured to impart turbulent forces on a pulp sample disposed within the inline mixer) configured to move in response to an external force, for example, an external power source or the force of the pulp sample on the mixing elements.

In the first dilution step 165, the initial pulp sample 115 and the dilution fluid 125 _(a) mix in the initial inline mixer 110 to create a first dilute pulp solution 127. In certain exemplary processes, ten parts dilution fluid 125 _(a) may be added per one part of initial pulp sample 115. For example, if the initial pulp sample 115 and dilution fluid 125 flow through the system 100 in liters per minute (“L/min”), operators can introduce the initial pulp sample 115 into the first inline mixer 110 at a rate of 1 L/min. Similarly, operators may introduce the dilution fluid 125 _(a) into the first inline mixer 110 at a rate of 10 L/min.

A portion of the first dilute pulp solution 127 _(a), typically having a pulp concentration of about 1% or less, flows from the first end 135 to the distal end 137 of a second pulp conduit 112 and thereby enters the feed end of a second inline mixer 120. The first end 135 of the second pulp conduit 112 engages the discharge end 111 of the first inline mixer 110 while the distal end 137 engages the feed end 119 of the second inline mixer 120. The second inline mixer 120 is disposed downstream of the first inline mixer 110 and has a discharge end 121 distally disposed from the feed end 119 along a body 105.

A first withdraw conduit 114 engages the first inline mixer's discharge end 111 at the first withdraw conduit's first end 145. The first withdraw conduit's second end 147 engages a withdraw line tank 124. The remaining first dilute pulp solution 127 _(b) flows through the first withdraw conduit 114 away from the serial pulp dilution system 100. In certain exemplary processes, the remaining first dilute pulp solution 127 _(b) may flow away from the serial pulp dilution system at a rate of about 10 L/min. In this manner, the first withdraw line 114 fluidly communicates with the first inline mixer 110 and is configured to withdraw the remaining portion of the first dilute pulp solution 127 _(b). As with all remaining portions of the dilute pulp solutions (127 _(b), 160 _(b), 170 _(b)) the remaining portion of the first dilute pulp solution 127 _(b) may be discarded. In other exemplary embodiments, the remaining portion of the dilute pulp solution 127 _(b), 160 _(b), 170 _(b) may be re-concentrated and reintroduced into the pulp process line (see 102) to mitigate waste.

In the second dilution step 175, additional dilution fluid 125 _(b) flows through a second dilution conduit 128 _(b) into the feed end 119 of the second inline mixer 120. The second dilution conduit 128 _(b) has a first end 133 and a distal end 155 distally disposed from the first end 133. The distal end 155 engages the feed end 119 of the second inline mixer 120. In certain exemplary processes, the additional dilution fluid 125 _(b) may be introduced into the second inline mixer 120 at a rate of about 10 L/min.

In the second inline mixer 120, the additional dilution fluid 125 _(b) and the portion of the first dilute pulp solution 127 _(a) mix to create a second dilute pulp solution 160. A portion of the second dilute pulp solution 160 _(a), typically having a pulp concentration of less than about 0.1%, flows through a third pulp conduit 118 into a third inline mixer 130 disposed downstream from the second inline mixer 120. The third pulp conduit 118 has a first end 142 engaging the discharge end 121 of the second inline mixer 120 and a distal end 146 engaging the feed end 129 of the third inline mixer 130. The third inline mixer 130 comprises a feed end 129 distally disposed from a discharge end 131 along a body 105.

The remaining portion of the second dilute pulp solution 160 _(b) flows through a second withdraw conduit 116 into a withdraw tank 124. A first end 144 of the second withdraw conduit 116 engages the discharge end 121 of the second inline mixer 120. A distal end 157 of the second withdraw conduit 116 engages the withdraw tank 124. In certain exemplary processes, the remaining portion of the second dilute pulp solution 160 _(b) may flow away from the exemplary serial pulp dilution system 100 at a rate of about 10 L/min.

Similarly, in the third dilution step 185, a further dilution fluid 125 flows through a third dilution conduit 128 into the feed end 129 of the third inline mixer 130. This further dilution fluid 125 may be introduced into the third inline mixer 130 at a rate of about 10 L/min. The third dilution conduit 128 has a first end 133 and a distal end 148 distally disposed from the first end 133. The distal end 148 engages the feed end 129 of the third inline mixer 130.

The further dilution fluid 125 and the portion of the second dilute pulp solution 160 _(a) mix in the third inline mixer 130 to create a third dilute pulp solution 170. A portion of the third dilute pulp solution 170 _(a), typically having a pulp concentration of less than 0.01%, flows through a fourth pulp conduit 126 into a fourth inline mixer 140 disposed downstream from the third inline mixer 130. The fourth pulp conduit 126 has a first end 154 engaging the discharge end 131 of the third inline mixer 130 and a distal end 158 engaging the feed end 139 of the fourth inline mixer 140. The fourth inline mixer 140 comprises a feed end 139 distally disposed from a discharge end 141 along a body 105. The remaining portion of the third dilute pulp solution 170 _(b) flows through third withdraw conduit 122 into a withdraw tank 124. A first end 152 of the third withdraw conduit 122 engages the discharge end 131 of the third inline mixer 130. A distal end 167 of the third withdraw conduit 122 engages the withdraw tank 124. The remaining portion of the third dilute pulp solution 170 _(b) may flow away from the serial pulp dilution system 100 at a rate of about 10 L/min. in certain exemplary processes.

Likewise, in a fourth dilution step, still further dilution fluid 125 _(d) flows through a fourth dilution conduit 128 _(d) into the feed end 139 of the fourth inline mixer 140. The fourth dilution conduit 128 _(d) has a first end 133 and a distal end 156 distally disposed from the first end 133. The distal end 156 engages the feed end 139 of the fourth inline mixer 140. The still further dilution fluid 125 _(d) and the portion of the third dilute pulp solution 170 _(a) mix in the fourth inline mixer 140 to create a fourth dilute pulp solution 180. The fourth dilute pulp solution 180 flows through a fifth pulp conduit 132 into a measurement device 136 disposed downstream from the fourth inline mixer 140. The fifth pulp conduit 132 has a first end 162 engaging the discharge end 141 of the fourth inline mixer 140 and a distal end 164 engaging the measurement device 136. In this manner, the initial pulp sample 115 may be extracted from pulp source 102 continuously and diluted by a factor of more than 1,500 prior to entering the measurement device 136. In other exemplary embodiments, the initial pulp sample 115 may be diluted 2,000 times or more prior to entering the measurement device 136. Depending upon the application, an exemplary serial pulp dilution system 100 may dilute the initial pulp sample 115 by 100 times or more, 450 times or more, 500 times or more, or 650 times or more.

In certain exemplary embodiments, the measurement device 136 may be a light microscope attached to a video camera and a monitor. The fourth dilute pulp solution may flow into the measurement device 136 at a rate of about 11 L/min. The light microscope and video camera may be configured to record the fourth dilute pulp solution 180 passing under the microscope and display the recording on the display. In this manner, operators may visually evaluate physical properties of the pulp fibers.

In other exemplary embodiments, the measurement device 136 may be an image analyzer.

Operators may control the rate at which dilution fluid 125 enters the several inline mixers 110, 120, 130, 140 using a series of valves V2-V6 disposed along the dilution conduit 128. In FIG. 1, V6 is the master valve. Operators may use V6 to control the access of dilution fluid 125 to all inline mixers 110, 120, 130, 140. V2 is disposed within the first dilution conduit 128 _(a), V3 is disposed within the second dilution conduit 128 _(b), V4 is disposed in the third dilution conduit 128, and V5 is disposed within the fourth dilution conduit 128 _(d). Operators may control the rate of dilution into the respective inline mixers 110, 120, 130, 140 using the respective valves V2-V5.

It is contemplated that in certain exemplary systems and processes, the initial pulp sample 115 may be extracted, diluted, and sent to a measurement device 136 in as little as three to five minutes after leaving the pulp source 102. Depending upon the processing speed of the measurement device 136, operators may obtain near real time data analysis of an active pulp line.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. 

What is claimed is:
 1. A continuous serial pulp sample dilution system comprising: a pulp source; a first sample conduit configured to transfer an initial pulp sample from the pulp source to a first inline mixer; a dilution fluid source; a first dilution conduit configured to transfer a dilution fluid to the first inline mixer, wherein the dilution fluid and the initial pulp sample mix in the first inline mixer to create a first dilute pulp solution; a second pulp sample conduit configured to transfer a portion the first dilute pulp solution from the first inline mixer to a second inline mixer; a first withdraw conduit configured to withdraw a remaining portion of the first dilute pulp solution from the first inline mixer; a second dilution conduit configured to transfer the dilution fluid from the dilution source to the second inline mixer, wherein the dilution fluid and the first dilute pulp solution mix in the second inline mixer to create a second dilute pulp solution being more dilute than the first dilute pulp solution; a third pulp sample conduit configured to transfer a portion of the second dilute pulp solution from the second inline mixer to a third inline mixer; a second withdraw conduit configured to withdraw a remaining portion of the second dilute pulp solution from the second inline mixer; and a third dilution conduit configured to transfer the dilution fluid from the dilution source to the third inline mixer, wherein the dilution fluid and the portion of the second dilute pulp solution in the third inline mixer mix to create a third dilute pulp solution being at least 100 times more dilute than the initial pulp sample.
 2. The continuous serial pulp sample dilution system of claim 1 further comprising a fourth pulp sample conduit configured to transfer a portion of the third dilute pulp solution from the third inline mixer to a fourth inline mixer; a third withdraw conduit configured to withdraw a remaining portion of the third dilute pulp solution from the third inline mixer; a fourth dilution conduit configured to transfer the dilution fluid from the dilution source to the fourth inline mixer, wherein the dilution fluid and the portion of the third dilute pulp solution mix in the fourth inline mixer to create a fourth dilute pulp solution.
 3. The continuous serial pulp sample dilution system of claim 1, wherein the first, second, and third inline mixers are static inline mixers.
 4. The continuous serial pulp sample dilution system of claim 1 further comprising a measurement device configured to receive the third dilute pulp solution from the continuous serial pulp sample dilution system.
 5. The continuous serial pulp sample dilution system of claim 4 further comprising a sample tank configured to receive the third dilute pulp solution, wherein the measurement device is configured to receive the third dilute pulp solution from the sample tank.
 6. The continuous serial pulp sample dilution system of claim 4, wherein the measurement device comprises a light microscope and a video camera linked to a video display or similar fiber analyzing equipment.
 7. The continuous serial pulp sample dilution system of claim 1 further comprising a recirculation conduit fluidly communicating with the first sample conduit and the pulp source, wherein the recirculation conduit is configured to convey a portion of the initial pulp sample from the first sample conduit back to the pulp source or some other use.
 8. The continuous serial pulp sample dilution system of claim 1 further comprising a pulp fluidly communicating with the pulp sample dilution system and configured to convey the initial pulp sample from the pulp source to the first inline mixer.
 9. The continuous serial pulp sample dilution system of claim 1 further comprising a dilution pump fluidly communicating with the pulp sample dilution system and configured to convey the dilution fluid from the dilution source to the first inline mixer.
 10. The continuous serial pulp sample dilution system of claim 1 further comprising dilution valves configured to selectively restrict an amount of dilution fluid injected into the inline mixers.
 11. The continuous serial pulp sample dilution system of claim 1 further comprising a pulp valve configured to restrict an amount of the initial pulp conveyed into the first inline mixer.
 12. A continuous serial pulp sample dilution system comprising: a pulp source; a first sample conduit configured to transfer an initial pulp sample from the pulp source to a first inline mixer; a dilution fluid source; a first dilution conduit configured to transfer a dilution fluid to the first inline mixer, wherein the dilution fluid and the initial pulp sample mix in the first inline mixer to create a first dilute pulp solution; a second pulp sample conduit configured to transfer a portion the first dilute pulp solution from the first inline mixer to a second inline mixer; a first withdraw conduit configured to withdraw a remaining portion of the first dilute pulp solution from the first inline mixer; a second dilution conduit configured to transfer the dilution fluid from the dilution source to the second inline mixer, wherein the dilution fluid and the first dilute pulp solution mix in the second inline mixer to create a second dilute pulp solution being more dilute than the first dilute pulp solution; a third pulp sample conduit configured to transfer a portion of the second dilute pulp solution from the second inline mixer to a third inline mixer; a second withdraw conduit configured to withdraw a remaining portion of the second dilute pulp solution from the second inline mixer; a third dilution conduit configured to transfer the dilution fluid from the dilution source to the third inline mixer; a fourth pulp sample conduit configured to transfer a portion of the third dilute pulp solution from the third inline mixer to a fourth inline mixer; a third withdraw conduit configured to withdraw a remaining portion of the third dilute pulp solution from the third inline mixer; and a fourth dilution conduit configured to transfer the dilution fluid from the dilution source to the fourth inline mixer, wherein the dilution fluid and the portion of the third dilute pulp solution mix in the fourth inline mixer to create a fourth dilute pulp solution being at least 450 times more dilute than the initial pulp sample.
 13. The continuous serial pulp sample dilution system of claim 12 further comprising a measurement device configured to receive the third dilute pulp solution from the continuous serial pulp sample dilution system.
 14. The continuous serial pulp sample dilution system of claim 13 further comprising a sample tank configured to receive the third dilute pulp solution, wherein the measurement device is configured to receive the third dilute pulp solution from the sample tank.
 15. The continuous serial pulp sample dilution system of claim 13, wherein the measurement device comprises a light microscope and a video camera linked to a video display or similar fiber analyzing equipment.
 16. The continuous serial pulp sample dilution system of claim 12, wherein the first, second, third, and fourth inline mixers are static inline mixers. 